Formulas for Various Areas

Formulas for Various Areas

Plane Figures

Area1

triangle

ab /2

parallelogram

ab

rectangle

ab

square

s 2

circle

π r 2

Solids

Total Surface Area1

right circular cylinder

2π r ( r + a )

right circular cone

π r ( r + l )

sphere

4π r 2

Footer

1&hairsp;The abbreviations used are: b &equals; base (length of any side of a plane figure); a &equals; altitude (perpendicular distance from the farthest point of the figure to the extended base); s &equals; side; r &equals; radius (of the base circle in the case of the cylinder or cone); l &equals; slant height (distance from vertex to base of a cone measured on its surface).